Simple resistor calculator by tapping or dragging buttons to assign colours to the resistor. In the Apple Watch app, the 3 sets of 4 buttons can be scroll horizontally by tapping forward and backward button to access all colour buttons.
The app provides 4 bands and 5 bands mode switchable.
In the iPhone app, swiping down with 2 fingers switches the mode of resistor. In the Apple Watch app, Force touch will show a context menu to select the mode.
Blue resister is for 5 bands and brown resistor is for 4 bands.
Apple Watch Glance is also provided and it shows current time with the resistor colours.